Stand boiler with vertical fire tubes and horizontal water baffles



Jan. 13, 1953 s. J. JAcoBY STAND BOILER WITH VERTICAL FIRE TUBES AND HORIZONTAL WATER BAFFLES Filed Jan. 2, 1951 FIGB.

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Patented Jan. 13, 1953 UNITED STATES PATENT OFFICE STAND BOILER WITH VERTICAL FIRE TUBES AND HORIZONTAL WATER BAFFLES Samuel J. Jacoby, St. Louis, Mo.

Application January 2, 1951, Serial No. 203,945

1 Claim.

Storage-type water heaters Ia-re prevalently utilized in vast numbers to provide a supply of hot water for personal, laundry and other usage, lboth in domestic and commercial installations. The present preference by the trade for water heaters of So-called high recovery rate, accentuates the problem to be described and particularly enhances the value of the present improvements. The problem solved by present improvements results from the tendency of extremely hot water and in many lcases steam, to rise along the one or more ues or flue tubes within the tank of the heater. This rapidly rising, relatively highly heated fluid many times results in formation of steam in the upper portion of the storage tank long prior to such time as the sensing element of the thermostat within the tank, calls for a reduction or cessation of heat from the source thereof. The situation Idescribed is obviously wasteful and inecient, and since in many cases the hot water is drawn from the upper portion of the tank, there resultsY an outiiow of -steam or under certain conditions excessively hot water. The present improvements accordingly haveas their principal and major objectives, the elimination of the shortcomings aforesaid, and the general improvement of efliciency of water heaters of storage tank type.

Yet another object of the invention is realized I in an improved arrangement of flue tubes and baille elements associated therewith, such as to result in a virtually complete and thorough admixture of the heated with the preheated water in a vstorage tank heater, as the heated water rises through the body of that in storage, thus conducing to a virtually even temperature of the warmed body of water in all parts of the tank.

A still further and important objective of the present improvements is realized in an improved arrangement of ue tubes and water bailies, and an optimum arrangement and location of the sensing element of a thermostat utilized with such an assembly, to obviate the diiiiculties rst above noted.

, The foregoing and numerous other objects and advantages will more clearly appearfromtheiol- 2 lowing detailed ldescription of a currently pref erred embodiment, particularly when considered in connection with the accompanying drawing, in which:

Fig. 1 is a vertical `sectional elevation taken Ain lan -axial plane of a vertical water storage heater;

Fig. 2 is a horizontal sectional View yas taken along line 2-2 of Fig. 1;

Fig. 3 is a horizontal sectional view as taken along line 3 3 of Fig. 1, and

Fig. 4 is a horizont-al sectional View as taken along line 4--4 of Fig. 1.

Referring now by characters of reference to the drawing, the tank proper includes an outer shell OS and an inner shell IS, both shown in cylindrical form Abut Without limitation to exact shape, and with the inner cylindrical wall spaced inside the outer suiiiciently to provide a Ispace therebetween for the accommodation -of thermal insulation INS. The outer tank is provided with a convex upper closure UC and an upwardly convex, downwardly concave bottom `closure or crown sheet CS at its lower er1-d. Both of the end closures lare suitably apertur-ed conformably to and in sealing relation with one or more vertical flues or flue tubes F. In the drawing these are shown in a plurality of four, in ya symmetri-cal arrangement, and with the axes of the several flue tubes F substantially equidistantly located from the vertical axis of the tank. Below the tank and .particularly below the crown sheet CS, is -a burner B for any suitable type of fuel, here shown as a gas burner provided with the usual automatic controls, valves, pilot and the like (not shown). The burner B is or may be, in well known manner, subject to an off-and-on control, or toa regulated throttling control of a thermostat generally indicated at T and characterized by an enclosed sensing element SE which preferably is located about as Ishown in Figs. 2 and 4. The burner is supplied by a gas supply line GSL (Fig. 1) Iand the tank assembly, as is conventional, is supported somewhat above floor level as by legs L.

In the upper portion of the outer tank, closed by a top cover TC, is a flue space FS whence the hot gases and production of combustion from the burner B `directed upwardly through ues F are consolidated and vdirected outwardly through a pipe P to the usual chimney or stack. A water inlet connection IC and a hot water outlet lconnection OC, are or may be conventional and are presently included for completeness of disclosure.

The embodiment of present improvements ina preferred form, .includes a vertical stack .of

f spacedbales, preferably of sheet metabthelow.-

ermost of the series of which is indicated at i0. For each of the iiues F there is provided in the baiile I an aperture of a size snugly to nt and closely to embrace the adjacent ue tube, the number of such apertures corresponding, in baiiie in, to the number of tubes. The baiiie I0 and other similar baiiies, may be Welded or otherwise nxedly attached to the ue tubes so as to be supported thereby, from which it will appear that any tendency of the one or more nue tubes to become bent or warped from thermal or other eifects, from an original vertical linear position, and in a multiple flue unit, thus to be brought out of parallelism with the companion nues, is obviated by the bridging and bracing eifect ofthe several baffles of the stack, such as IU and others to be described. It will be noted as from Fig. 3, that the peripheral margin, or at least a substantial portion of such margin, is spaced from the nearest tank wall, being the inner cylindrical surface'of the inside tank. This spacing as will appear, permits water circulationbetween marginal portions of the baiile, and the adjacent wall of the tank as the heated water moves upwardly.

It is a preference thatthe vertical spacing of adjacent bailies be at least such as to amount to two or three times the diameter of the individual tubes. The next adjacent baille proceeding upwardly of the stack, and indicated at il, is

or may be similar in all respects as to structure f and attachment, to the bafiie lil, with the exception that bafiie Ii is preferably provided in a multiple ue heater with a large central opening I2. The area of such opening and its locationare such as to conduce to a flow of the heated water originally proximate to the tubes, in a direction radially inwardly of the tank, thence upwardly through the opening i2, thence impinging the next baiile of the series indicated at IB. Since this latter is imperforate except where traversed by the flue tubes, the heated water is again compelled to proceed to the free marginal portions of the baiile and so to move radially outwardly of the tank as itrmoves across thefree margins of the next baiile I9.

The baiiles IB through the seriesarefpreferably intervened by thebaiiies H with a repetition of the circulatory and directive effects above described. Thus it will be seen that the column or columnsv of heated water warmed through the crown sheetv CS'and the several ue tubes F, will result infan inward, thence outward, thence inward movement of the water with respectI to the axis ofa vertical-tank, as shown by the arrows (Fig. l). Otherwise expressed, there results a rig-zag travel` of the heated-column orcolumns of water rising throughthe tank.

It is al preference that the first baffle I0 of the series be imperforate rather than lperforate; similarly, that the uppermost baiiieof the series I3 be imperforate, so as to supply thetakeoff or upper portion of the tank, with water vwhich has-been subjected to an unusual extent of lineartravel as same rises through thev tank.

Numerous experiments havebeen madewvith diiferent locations, in the present baiiieand tube assembly, of the. sensing element SE'of the thermostat controlling the burner B. It has `been found conducive to a more uniform water tem'- perature throughout theA tank to locate such a sensing element about as-.shown by Figs.- 1 and 4;,- with the elementV SE extended radiallyv and horizontally into the central or..l axis region of the tank, andso. that theelement: SE islocated aboutamidway.. vertically. .between the. firstl and.

second baiiles I0 and Il proceeding from the bottom of the stack. While such location is by no means critical, it has been found highly advantageous as reflected in better heating eiiciency and greater uniformity of water temperature throughout the tank.

It is preferred as a matter of simplicity of formation to construct each of the baiiies lil and Il so that it conforms substantially in shape to the section of the water-conning wall of the tank, these elements being respectively circular and cylindrical but with the described spacing of the baiie margins inwardly of the tank wall. Obviously, if 'desired for structural or other reasons, restricted portions of the margin of the baiiles may' extend to the inner tank wall, and thus enhance thebridging and bracing functions of the baille. Thus there are distinctly contemplated, but without limitation, the possibility of serrato or scalloped baiiie margins or other desired formation thereof (not shown).

The present improvements probably exhibit their greatest operating advantages in a multiple nue type of automatic storage heater assembly; it will, however, be understood that the improvements are of considerable advantage when uti.- lizing but a single central'iue tube in which case as in the present, the alternate perforate baffles will be punched or otherwise apertured so that their circulatory apertures are remote lfrom the flue and located in the present structure substanftially inwardly of the outer margins of the baiiie.

it will have appeared that irrespective of any reasonably high combustion rate of the burner B tending with present constructions to drive upwardly, a rapidly moving column ofV water and steam along the exposed metal surfaces of the several ue tubes, there will not, as prevalently, result a steam pocket at the top of the tank proper; in fact the lateral circulatory movement imparted-to the upowing heated water will serve to mix the heated'water with the cool water from supply connection IC, as well as with the whole body of the water in the tank, thus preventing any flash steam formation and resulting, as has been proven, in an approximate uniformity of temperature through the tank. This result is further1 assured, and any appreciable cold Water column. avoided in the tank, by the utilization of a lowermost imperforate baffle plate lili Such an arrangement provides. as clearly appears inv Fig. l, a tempering chamber separate from the space thereab'ove except for the annular space peripherally of the lower baffle. The incoming (cold water supply, preferably directed transversely of this. chamber across the warmest lengths of the tubes F, will quickly bring-thesupply liquid to desired temperature.'-

Although the invention has been described by detailed reference to theelements of a single preferred embodiment of theinvention, the detail of description is to be understood-solely in an informative, rather than in restrictive sense, numerous variants being possible within the scopeof the claim hereunto appended.

I- claim as my invention:

In a storage typewater heater characterized'by a vertical tank, the tank consisting of double spaced walls andV provided' with-1 thermal insulation between` said walls, a, crown sheet at: the lower portion ofthe water-containing portion of the tank, aplurality of iue tubes extending through the crown sheet then vertically through the water-storage space-of the tank, a. nue space providedabove theV ue tubes, an outer. flue di rected from said flue space, water inlet and outlet connections to the water space of the heater, a series of vertically spaced substantially horizontal plates serving as bailes located in the water space of the tank, each of said baies conforming substantially in shape to the section of the Water-conning wall of the tank, but being appreciably spaced inwardly therefrom, and each apertured to receive and closely to embrace the several vertical flue tubes, the lowermost of the plates of said series being imperforate except for flue tube apertures therein, and providing with the crown sheet, a substantially closed, coldwater-tempering chamber open only peripherally of the lowermost plate into the storage space thereabove, the water inlet connection opening into the tempering chamber, theY next superjacent baie plate being provided with a central aperture equdistantly spaced from the several flue tubes and substantially remote therefrom, the remaining baffle plates of said stack being alternately imperforate and perforate as described, apart from flue openings therein, whereby to promote a circulation of heated water alternately toward the outside of the tank, then toward the interior of the tank, thus providing a zig-zag path of travel of heated water upwardly of the tank; the several flue tubes having their exterior surfaces within the tank directly exposed to the body of water therein, and a tankV REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 104,511 Tillman June 21, 1870 681,244 Mott Aug. 27, 1901 721,310 Junkers Feb. 24, 1903 890,237 Kennepohl June 9, 1908 948,835 Walter Feb. 8, 1910 1,609,822 Jefferson Dec. 7, 1926 1,641,999 Webster Sept. 13, 1927 1,900,857 Berry et al. Mar. 7, 1933 2,066,190 Swars Dec. 29, 1986 2,440,998 Alexander May 4, 1948 

